This document summarizes the work of the SDC Cross-project team. We have analyzed a selected set of the Freight Mobility Initiative (FMI) data from ATRI, as well as crowdsourced traffic incident reports from the Waze for Cities feed. For comparison purposes, an area of eastern Massachusetts was selected for September 2019.
All code is version-controlled in the FMI_Waze repository on GitLab within SDC.
Main takeaways:
The following maps show aggregated counts of unique truck IDs per hour and counts of Waze events per hour. The spatial unit is 1-square mile hexagonal grid cells. An alternative approach to pursue in the future is to assign each event to a road segment.
These maps further aggregate the count to daytime (7 am to 7pm, Eastern) and weekend/weekday time periods for ease of comparison.
Note these maps compare just weekday and weekend time periods for mean speeds of unique truck IDs within a grid cell. The mean speed of a given truck ID was first calculated; these values are the means of those mean values by truck ID.
Each point below represents one grid cell. Values are the sum of distinct truck IDs or unique Waze alerts for the specified time frame in that grid cell.
The following plot and table demonstrate that the two data sets can be combined in useful ways. When at least 3 jam reports are present in the Waze data, there is a dramatic drop in the speeds of trucks in the FMI data. The boxplots below group truck speeds into five categories, and the y-axis represents the mean count of distinct truck IDs per grid cell for that time period and number of jams. Note that ‘low jams’ represents most of the data, 92,675 grid cells x weekend/weekday time period, while ‘high jams’ is a less common condition, only 8,465 grid cells x weekend/weekday time period.
| weekend | high_jams | Number of grid cell x time combinations | Median FMI truck speeds | Sum FMI truck counts | Median Waze jam reports | Sum all Waze reports |
|---|---|---|---|---|---|---|
| Weekday | High Jams | 6,593 | 15 | 435,550 | 10 | 232,675 |
| Weekday | Low Jams | 55,529 | 28 | 4,417,368 | 0 | 171,390 |
| Weekend | High Jams | 1,872 | 31 | 26,228 | 6 | 25,568 |
| Weekend | Low Jams | 37,146 | 34 | 831,279 | 0 | 42,885 |